Can the XBee’s TX and RX pins support 5V signals? I read in Making Things Talk that they could, but the Maxstream site says they can’t. I have a Series 1 Xbee withe a wire antenna.[/quote]
I don’t think so… 
I’ve talked with Maxstream tech support about this. Even though the XBee modules can survive 5V for a short, undefined period of time, they will soon degrade and become unoperable.
Yes, I meant Maxstream not Digi - Maxstream had one of the best support structures I’ve ever seen. When Digi took over, that was one of the first things they did away with.
I don’t know about today, but many months after Digi acquired Maxstream, tech support was still good.
Yours is a basic question - answered by reading the spec sheet.
Okay, let me rephrase that.
What is your experience with 5V IO signals on the XBee?
You’re right, a few months after the acquisition it was the same. However, they did away with the instant online chat support after the restructuring was complete and now you’ve got to wait a day or so for a simple question. It really sped up my company’s dev time being able to have their engineers so readily accessible. I have to say, though, I’m not sure it was economically advantageous, but I hope it was because we go through their modules like water now.
I connected the XBee on a 3.3V rail to a 5V system thinking it was 3.3V. After I discovered the voltage error, it had been working OK for a day or two. I decided to give Maxstream a chat about it. The answer was yes, it works but it won’t for long. Your definition of “long” is as good as mine.
No. it is dangerous. a guy input 5 voltage signal, so the xbee is blow.